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1). If you haven't clipped out the Varta CMOS barrel battery yet, do it now! If they haven't burst and spewed acid all over the motherboard yet, they will at some point. And you don't need to solder in a new barrel battery. The motherboard has the leads for an external battery, you can do like I did and connect a little battery box w/2 AA batteries in it.

2). Don't forget to upgrade the onboard video RAM if you haven't already.

3). If you need a little speed burst you can install a 50MHz Cyrix 486 SRx2 "snap-in" upgrade. Note that if you install the SRx2, there won't be enough room between the CPU and the drive cage to install the heatsink it comes with. I overcame this by using a thermal pad to adhere a thin copper heatsink to the CPU.

4). I installed a Sound Blaster CT-1350 in my Mega PC's free ISA slot, and used the FM jumper to disable the YM3812. This way there's only one device outputting Ad Lib music/sound: the Mega PC itself. The Sound Blaster meanwhile outputs DAC and Game Blaster sound (via the C/MS upgrade).

5). You can carefully remove the slider on the front of the case, to switch between PC and MD modes quickly and easily (and w/o having to remove a cart and control pads every time you want to run a DOS game!)

Last edited by DeathAdderSF; October 20th, 2018 at 12:36 AM.

WANTED: Covox Sound Master, IBM 3D Sound PCMCIA
Please contact me if you have either of these for sale! Thanks.

1). If you haven't clipped out the Varta CMOS barrel battery yet, do it now! If they haven't burst and spewed acid all over the motherboard yet, they will at some point. And you don't need to solder in a new barrel battery. The motherboard has the leads for an external battery, you can do like I did and connect a little battery box w/2 AA batteries in it.

2). Don't forget to upgrade the onboard video RAM if you haven't already.

3). If you need a little speed burst you can install a 50MHz Cyrix 486 SRx2 "snap-in" upgrade. Note that if you install the SRx2, there won't be enough room between the CPU and the drive cage to install the heatsink it comes with. I overcame this by using a thermal pad to adhere a thin copper heatsink to the CPU.

4). I installed a Sound Blaster CT-1350 in my Mega PC's free ISA slot, and used the FM jumper to disable the YM3812. This way there's only one device outputting Ad Lib music/sound: the Mega PC itself. The Sound Blaster meanwhile outputs DAC and Game Blaster sound (via the C/MS upgrade).

5). You can carefully remove the slider on the front of the case, to switch between PC and MD modes quickly and easily (and w/o having to remove a cart and control pads every time you want to run a DOS game!)

Thanks for the info.

1) The original battery still works, but I'll eventually clip it out. I have already done it with the other Mega PC which I keep as a spare.
2) I have already checked for the video RAM. It seems to be a kind of generic memory chips that still can be bought for a couple of dollars a piece. Where did you get your video memory?
3) I probably won't do this upgrade.
4) I have a soundblaster CT4170 which I use in my other 386 computer (requires program to set IRQ stuff as this is a Plug'n'play card without jumpers), I might try the thing with the FM jumper.
5) I'll check that mod out, but I don't really like to butcher the Mega PC.